Question

Assume that a 4-bit serial in/serial out shift register is initially clear. We wish to store the nibble 1100. What will be the 4-bit pattern after the second clock pulse? (Right-most bit first)

(a) 1100

(b) 0011

(c) 0000

(d) 1111

The question was asked at a job interview.

Asked question is from Shift Registers topic in division Registers of Digital Circuits

Answer 1

The correct choice is (c) 0000

For explanation: In Serial-In/Serial-Out shift register, data will be shifted one at a time with every clock pulse. Therefore,

Wait | Store

1100 | 0000

 110 | 0000 1st clock

  11 | 0000 2nd clock.